The Netherlands international has yet to feature for Roberto Martinez's side in the Premier League this season and, with the FIFA World Cup set to take place in Brazil next year, Heitinga is keen for regular first-team football to boost his chances of being named in the Dutch squad.
Sam Allardyce's West Ham are seeking defensive reinforcements with James Collins, Winston Reid and James Tomkins all suffering injuries, and have been linked with a move for the 30-year-old.
And Heitinga admits that he will need to consider his future with the January transfer window set to open on Wednesday.
"I am flattered with the interest of West Ham," he told Voetbal International.
"Since this week the market is open and it's clear that I have to make an important decision.
"The chance of playing more minutes is the most important. I want to be at the World Cup and, to realise that, I have to play.
"Only then can I make it difficult for (Netherlands coach) Louis van Gaal."
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